[SRU][J][PATCH 0/1] change default to spec_store_bypass_disable=prctl spectre_v2_user=prctl

[Jeff Lane]

BugLink: http://bugs.launchpad.net/bug/1980160

[IMPACT]
A cloud workload team is reporting a performance hit with non-priviledged 
containers.

This happens due to default containers run with seccomp and that turns on 
spec_store_bypass (tested on Ice Lake and Sapphire Rapids server)

Switch the kernel default of SSBD and STIBP to the ones with CONFIG_SECCOMP=n 
(i.e. spec_store_bypass_disable=prctl_spectre_v2_user=prctl) even if 
CONFIG_SECCOMP=y.

There is a much longer explanation in the patch commit message.

Picks cleanly to 5.15

Requested by Intel

[HW/SW Information]
Target Kernel: 5.16
Target Release: 22.04
Ice Lake and Sapphire Rapids server platform

[Business Justification]Upstream performance fix

[FIX]
2f46993d83ff4abb310ef7b4beced56ba96f0d9d


Andrea Arcangeli (1):
  x86: change default to spec_store_bypass_disable=prctl
    spectre_v2_user=prctl

 Documentation/admin-guide/hw-vuln/spectre.rst   | 10 ++++------
 Documentation/admin-guide/kernel-parameters.txt |  5 ++---
 arch/x86/kernel/cpu/bugs.c                      |  4 ++--
 3 files changed, 8 insertions(+), 11 deletions(-)

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2.34.1